free 3D design tool

[fresun]

Hey just a quick note,
Using free Google sketchup 3D design software to plan panel position and even shadowing throughout the day/year. Have a look. It takes a little practice but all the tutorials are there.

This is my first design for my bungalow and MSC assesment hopefully. I Had hoped to use some of the south facing roof, which is shaded from house next door on lower 50% and from nov-feb roughly speaking. Even using solar edge optimizers I have discovered they still need minimum of 6 panels per string to power inverter to grid export. I am now looking at this East West split 6+6 hyundai 250w panels and two SMA1300 inverters.

To view my project and use sketchup, download the free version. Watch a few how to videos and your away.

Any advice from more experienced installers would be much appreciated. Use sketchup help to learn about shadow tool use, amazing for a freebie.

I can't seem to attach my Sketchup document right now TBC
Cheers



Lifes a Beech Y

 

[Worcester]

As it's google sketchup - why not share it via google drive and either post the url or if it won't let you do that (you might have to have a certian number of posts) write it out tlike this; go to: google dot co dot uk

to make sharing simpl, you could even create a goo dot gl link (yes thats goo.gl ) it's a shortener owned by googgle

 

[BruceB]

Yes sketchup is good and I have used it to geo-locate models and see the effect of shading. It certainly got me one job because I was the only bidder that had overtly considered how the strings should be wired to minimise the effect of shadow from a ridge and included some screen shots in the proposal.

For an east-west installation, run the numbers on a dual mppt inverter like the Power One PVI 3.0 OUTD. One of those is almost certainly cheaper than x2 smaller single mppt ones.

 

[fresun]

Thanks Worcester for computer skill insight.

Here is the Google drive link to my Bungalow PV design: https://docs.google.com/file/d/0B1AksJacpE80TXBGWWxKVWdOems/edit?usp=sharing

Iceage
Ironage
Solarage

 

[fresun]

Hmm just tested that link (after posting sorry) no go?
Going to try the other suggestions. Thanks for your patience

 

[fresun]

This is the goo.gl shortened URL however, strangely when pasted into browser only returns random chinese like links. but when on the goo.gl page my document is displayed?
What is going on?
http://goo.gl/6vawU

 

[BruceB]

Not sure whether you have altered the link since you first put it up, but it works for me as a sketchup model.

You have only used half the roof with a mixture of portrait and landscape panels, which is tricky to get looking good aesthetically. Have you only used half the roof because it is a semi rather than detached house? If the drawing is right, the house is orientated 13 degrees (ish) west of south, which means the east facing slope is better orientated to get sun than the west facing slope by 26 degrees. The south facing hip is only compromised by shadow Nov-Feb, which is not much in the scheme of things.

I think your two options are:
- an east-west solution as you have done
- a south and east solution using solar edge, with perhaps additional west panels as well up to whichever is your limit (DNO limit, FIT boundary or money)

 

[fresun]

Thanks for feedback BruceB,

Yes We are semi-detached, I made the orientation 11' of true north using the compass on the smart phone, however It may be more accurate in the future, to take the suns angle at NOON GMT to guage true north, then measure deviation of the property with a protractor.

I concur with you for preference to the east roof, hence my design incorporating maximum panels of mixed orientation(land/port), I have not yet investigated using panels of different sizes, I assume a power one inverter would cope with that?

I have updated the sketchup model with a more accurately sized neighbours house. I Imagine to produce a number backed, accurate shading analysis, it would be possible to zoom in and measure percentage of panel shade throughout the day/ year so on, similar to the way a sunpath chart quantifies the obstacles on the horizon and giving a shade factor. I dare say PV sol type software to name one, does this calculation for you?

Latest Model
http://goo.gl/PTdlL

Thanks Dunc

 

[BruceB]

Do not use panels of different sizes unless you really know what you are doing. Simplifying a bit but on each mppt all the panels must be same type/size/azimuth/elevation.

Do you apreciate the advantages of Solar Edge in this situation?

Depending on where you are, remember to use local noon rather than GMT.

You will find that zoopla and similar orientate their visual mapping to north, which might be the simplest way to measure it.

Others will have to answer about pvsol.

 

[fresun]

Being in SE Essex we're only 0.7' of GMT.

I made a mistake on 3D model, forgetting my property sits 900mm lower than the neighbours house due south. It seems now that only after late march are the south array clear of shade completely.

It does seem a shame to lose the south roof completely. However the tech guy at Solar edge insists 6 panels minimum per string or roof to energise inverter.

With no experience despite having the qualifications I am resorting to drawing on you guys hard earned knowledge, else this type of survey could lead into rocket science mathmatics:

thinking power per pound, would using solar edge: string of say 10 but split over East and south, more cabling perhaps. Or keep it simple With an East west and a dual mppt. S1

Thanks again D
http://goo.gl/qeENw